Brazilian President Luiz Inacio Lula da Silva is in Havana for a 24-hour visit to strengthen economic ties with Cuba.
Brazilian President Luiz Inacio Lula da Silva has met ailing Cuban leader Fidel Castro, who has not been seen in public for more than 17 months.
President Lula is expected to sign a series of trade and investment agreements with Communist-run Cuba, in defiance of the US economic embargo.
They held a private meeting in Havana at the end of Lula's 24-hour visit to the communist state, which was aimed at boosting economic ties.
These include an extension of credit lines to allow Cuba to buy more food from Brazil, and investment in Cuba's oil, transport and tourism sectors.
It had been unclear until the last minute whether the two would meet.
Lula also hopes to see his ailing Cuban counterpart, Fidel Castro.
Lula signed agreements with the acting Cuban President, Fidel's brother Raul, including an aid package.
Since the collapse of its main benefactor the Soviet Union, Cuba has struggled to survive, particularly with the US tightening its trade embargo. Venezuela and China are now Cuba's biggest trading partners, offering easy credit terms and subsidised oil.
The package includes up to $1bn in credits.
Friend
The Brazilian deal will help Cuba increase its food imports and improve parts of its infrastructure.
During his short visit, President Lula is expected to offer a helping hand from what is one of Latin America's largest economies.
Cuba also secured a commitment from the Brazilian state oil company, Petrobras, to search for oil reserves in Cuban waters.
Fidel Castro has not appeared in public for almost 18 months
Brazilian influence
Brazil's left-wing president also hopes to see Fidel Castro, whom he describes as a personal friend.
Lula's visit was seen as an attempt by Brazil to improve ties with Cuba, and enhance its regional influence, which has been overshadowed by Venezuelan President Hugo Chavez.
A number of Lula's closest allies were exiled in Cuba during Brazil's 1964-1985 military dictatorship. This is his second visit to the island since taking over the presidency in 2003.
Fidel Castro has undergone a series of stomach operations
But it is not clear whether the meeting will take place.
Since the collapse of its main benefactor the Soviet Union, Cuba has struggled to survive, particularly with the US tightening its trade embargo, the BBC's Michael Voss reports from Havana.
President Lula's spokesman Marcelo Baumbach, said that "because of Fidel's health situation we are relying a little on his doctor's opinion".
Venezuela and China have become its biggest trading partners, offering easy credit terms and subsidised oil.
Fidel Castro, 81, has not been seen in public for almost a year and a half after undergoing a series of intestinal operations.
A number of Lula's closest allies were exiled to Cuba during Brazil's 1964-1985 military dictatorship.
He has been writing regular newspaper editorials and has been photographed meeting a number of visiting politicians, including Venezuela's President Hugo Chavez.
It was the Brazilian president's second visit to the island since taking over the presidency in 2003.
The most recent update of Fidel Castro's health came in late December from his brother and acting head of state, Raul Castro.
Key figures
He said his brother Fidel was mentally alert, had put on weight and was exercising for two hours twice a day.
Fidel Castro, 81, has not been seen in public since undergoing a series of intestinal operations.
President Lula's visit was scheduled to taken place last year but was postponed several times.
He has been writing regular newspaper editorials and has been photographed meeting a number of visiting politicians, including Mr Chavez.
The official reason given by the Brazilians was that more time was needed to work out this complex set of trade and investment deals.
The most recent update of Fidel Castro's health came in late December from Raul Castro.
Biofuels
He said his brother was mentally alert, had put on weight and was exercising for two hours twice a day.
Lula and Fidel are two of the leading lights of left-wing politics in Latin America, but occupy different parts of the political spectrum.
Lula and Mr Castro are two of the leading lights of left-wing politics in Latin America, but occupy different parts of the political spectrum, our correspondent adds.
President Lula is considered part of what is known as the pragmatic left in Latin America.
Lula is considered part of what is known as the pragmatic left in Latin America.
Cuba is going through a period of change
He supports a free market economy at home and maintaining good relations with the US - a position radically different from that of Cuba and Hugo Chavez.
He supports a free market economy at home and maintaining good relations with the US. It is a position radically different from that of Cuba and its closest regional ally, Hugo Chavez in Venezuela.
There have also been disagreements between Cuba and Brazil over biofuels.
There have also been disagreements recently between Cuba and Brazil, particularly over biofuels.
Fidel Castro has written extensively against the use of agricultural crops for biofuels of which Brazil is one of the world's leading producers.
Fidel Castro has written extensively against the use of agricultural crops for biofuels of which Brazil is one of the world's leading producers.
This is a critical period of transition in Cuba, with Fidel still recuperating and Raul attempting to push through a series of economic reforms while maintaining the one-party state.
President Chavez's failed referendum in Venezuela was a timely reminder to the Cubans about the potential risks of tying themselves too closely to a single benefactor.
President Lula's offer of additional trade and investment from Brazil could help Cuba's leadership in maintaining economic stability on the island during this period of change,
